On the first 3 exams of her language class, Jessica got an average score of 82. What does she need on the next exam to have an overall average of 86?
Let her score on the next exam be $x$ The sum of all of her scores is then $3 \cdot 82 + x$ The same sum must also be equal to $4 \cdot 86$ Solve: $x = 4 \cdot 86 - 3 \cdot 82 = 98$.